Head and neck conditions Flashcards
one of the commonest neonatal facial anomalies. In ~80% of cases, the two features tend to occur together
Cleft lip and palate
Associations of cleft lip and palate :
aneuploidic syndromic: tends to occur with types II, III and IV 5
- trisomy 13
- trisomy 18
non-aneuploidic syndromic
frontonasal dysplasia
Gorlin syndrome
Kallmann syndrome
Stickler syndrome
TAR syndrome
VACTERL association
fetal valproate syndrome
non-aneuploidic non-syndromic
- Dandy-Walker continuum
- holoprosencephaly: often with type
IV
- pentalogy of Cantrell
MOST common location of cleft lip and palate?
majority are unilateral and 70% of these are on the left.
What uss feature can be seen with cleft lip and palate?
there can be polyhydramnios if the defect is severe and impairs swallowing
What is the most common type of facial fractures, accounting for ~45% of facial fractures, and are often missed when significant facial swelling is present.
WHat is the second most common facial bone fracture?
Nasal bone fractures
Zygomaticomaxillary complex (ZMC) fractures
midface fractures which collectively involve separation of all or a portion of the midface from the skull base. In order to be separated from the skull base, the pterygoid plates of the sphenoid bone need to be involved as these connect the midface to the sphenoid bone dorsally.
Le Fort fractures
WHat are the three types of le fort fractures
- Le Fort I is a floating palate (horizontal) - fracture line passes through the alveolar ridge, lateral nose and inferior wall of the maxillary sinus
- Le Fort II is a floating maxilla (pyramidal) - fracture arch passes through the posterior alveolar ridge, lateral walls of maxillary sinuses, inferior orbital rim and nasal bones
- Le Fort III is a floating face (transverse) - transverse fracture line passes through nasofrontal suture, maxillo-frontal suture, orbital wall, and zygomatic arch/zygomaticofrontal suture
Zygomaticomaxillary complex (ZMC) fractures, also known as tripod, tetrapod, quadripod, malar or trimalar fractures, are seen in the setting of traumatic injury to the face. They comprise fractures of the:
zygomatic arch
inferior orbital rim, and anterior and posterior maxillary sinus walls
lateral orbital rim
Sinonasal inflammatory conditions include?
acute sinusitis
- Pott puffy tumour
chronic sinusitis
fungal sinusitis
– non-invasive: hyphae do not invade mucosa
- allergic fungal sinusitis
- sinus fungal mycetoma
– invasive: hyphae seen invading mucosa +/- beyond
- acute invasive fungal sinusitis
- chronic invasive fungal sinusitis
- granulomatous invasive fungal
sinusitis
granulomatosis with polyangiitis (formerly known as Wegener granulomatosis)
sinonasal polyposis
an acute inflammation of the paranasal sinus mucosa that lasts less than four weeks and can occur in any of the paranasal sinuses.
WHat are the common findings on CT?
Acute sinusitis
peripheral or central mucosal thickening
gas-fluid levels in the paranasal sinuses
gas bubbles within the fluid / / bubbly secretions
obstruction of the ostiomeatal complexes.
What are the complications of acute sinusitis ?
erosion through bone
subperiosteal abscess
frontal sinus superficially (Pott puffy tumour)
frontal or ethmoidal sinuses into the orbit (subperiosteal abscess of the orbit)
dural venous sinus thrombosis
intracranial extension
meningitis
subdural empyema
cerebral abscess
refers to a non-neoplastic complication of acute sinusitis. It is characterised by a primarily subgaleal collection, subperiosteal abscess, and osteomyelitis. It is usually related to the frontal sinus but is sometimes secondary to mastoid pathology.
Rarer aetiologies include trauma, intranasal cocaine, and methamphetamine abuse, and craniotomy.
Pott puffy tumour
MOST common infectiuve agents of pott puffy tumour?
Streptococcus spp.
Haemophilus influenzae
Staphylococcus spp.
Klebsiella sp.
Chronic sinusitis is defined clinically as a sinonasal infection lasting more than 12 weeks. Causes include:
MOST common anatomical variant found in chronic sinusitis?
paranasal sinus anatomical variants obstructing drainage (see below)
sinonasal polyposis
chronic allergy
chronic infection:
chronic bacterial sinusitis
chronic allergic fungal sinusitis
cystic fibrosis
odontogenic
oncha bullosa (30%)
posterior nasal septal deviations (25%)
uncinate process variations (25%)
paradoxical middle turbinate (10%)
agger nasi cells (10%)
Haller cells (9%)
What are the two groups of fungal sinusitis?
two groups, depending on the presence of fungal hyphae within or beyond the mucosa:
INVASIVE
allergic fungal sinusitis
sinus fungal mycetoma
NON-INVASIVE
acute invasive fungal sinusitis
chronic invasive fungal sinusitis
granulomatous invasive fungal sinusitis
most common form of fungal sinusitis and is common in warm and humid climates.
Associated with ? (65% of cases)
allergic fungal sinusitis
Asthma
MOST common location (sinuses) for allergic fungal sinusitis?
The ethmoid sinus is the most common location, followed by the maxillary, frontal, and sphenoid sinuses.
indolent and non-invasive fungal colonisation of the paranasal sinuses.
Paranasal sinuses mycetomas, or fungus balls
What is the most aggressive form of fungal sinusitis. It is seen particularly in immunocompromised patients and is the source of significant morbidity and mortality
Acute invasive fungal sinusitis
Acute invasive fungal sinusitis imaging features?
What are the possible complications
acute infection generally does not demonstrate hyperdense material within the sinus on non-contrast CT
Aggressive surgical debridement is usually required.
Complications include:
intraorbital extension
intracranial extension
leptomeningeal enhancement
intracranial granulomas
epidural abscess and empyema
vascular invasion
cavernous or dural venous sinus thrombosis
mycotic aneurysm formation
cerebral infarction or haemorrhage
systemic dissemination
How do you distinguish chronic invasive fungal sinusitis from acute?
CHRONIC has longer clinical history (usually more than 12 weeks) 5
hyperdense material within the sinus is more common
sclerotic changes to the bony walls of the affected sinuses representing chronicity of the disease
represents maxillary sinus atelectasis that results in painless enophthalmos, hypoglobus and facial asymmetry
Silent sinus syndrome
What are the CT features of silent sinus syndrome?
The sinus is fully formed but fully opacified and reduced in volume with inward bowing of all four walls.
form of neural tube defect and a type of cephalocele where brain tissue and overlying meninges herniate out through a defect in the cranium.
Frontoethmoidal encephaloceles are more common in the south and south-east Asian populations.
encephalocele
Occipital encephaloceles may be associated with a number of additional abnormalities:
Chiari malformations
Dandy-Walker malformations
Meckel-Gruber syndrome
Frontoethmoidal encephaloceles manifest as a clinically visible mass where?
Basal encephaloceles are internal and are not generally externally visible, although they may manifest as a lump or bump in the oropharynx or nasopharynx.
along with the nose
The intracranial root of most frontoethmoidal encephaloceles lies at the foramen caecum, a small ostium located at the bottom of a small depression anterior to the crista galli and formed by the closure of the frontal and ethmoid bones
Rare cause of airway obstruction.
refers to narrowing of the pyriform aperture and results from early fusion and hypertrophy of the medial nasal processes.
MOST common associations?
Pyriform aperture stenosis
alobar and semilobar forms of holoprosencephaly
facial haemangiomas
clinodactyly
pituitary dysfunction
central megaincisor (in 75% of cases)
refers to a lack of formation of the choanae, the openings providing communication between the nasal cavity and nasopharynx. It can be unilateral or bilateral.
Associations?
Choanal atresia
Syndromic associations include
CHARGE syndrome
Crouzon syndrome
DiGeorge syndrome
amniotic band syndrome
fetal alcohol syndrome
Treacher Collins syndrome
Other associations include
intestinal malrotation
craniosynostosis
congenital heart disease
commonest causes of nasal obstruction in neonates
Choanal atresia
common incidental benign midline nasopharyngeal mucosal cysts
Tornwldt cyst
Imaging features of Thornwaldt cyst?
Typically they are well circumscribed rounded lesions immediately deep to the mucosa. They are usually nestled between and anterior to the longus colli muscles they elevate the mucosa forming a convex surface into the nasopharynx. They are variable in size, ranging from a few millimetres to a few centimetres in diameter, but are typically 2-10 mm in size
refers to the presence of multiple benign polyps in the nasal cavity and paranasal sinuses.
Sinonasal polyposis
Conditions known to be associated with nasal polyps?
Conditions known to be associated with polyps include:
infectious rhinosinusitis
cystic fibrosis
allergic fungal sinusitis
asthma
nickel exposure
eosinophilic granulomatosis with polyangiitis
solitary sinonasal polyps that arise within the maxillary sinus (antrum). They pass through and enlarge the sinus ostium and posterior nasal cavity at the level of the choana.
Antrochoanal polyp
complete opacification of one or more paranasal sinuses by mucus, often associated with bony expansion due to obstruction of the nasal sinus drainage.
Paranasal sinus mucocele
Mucoceles distort local anatomy and exert pressure on adjacent structures as they enlarge. Examples include:
frontal mucocele extending into the front of the orbit, presenting as a mass
posterior ethmoidal mucocele compressing the orbital apex
sphenoidal mucocele extending posteriorly to impinge on the pituitary gland and brainstem
maxillary mucocele may elevate the orbital floor with resultant proptosis
MOST common location for paranasal sinus mucocele?
The frontal sinus is particularly prone to developing mucoceles, and up to two-thirds of all mucoceles occur there. The ethmoidal sinuses are the next most common (~25%), whereas the maxillary and sphenoid sinuses are infrequently involved
Imaging features of paranasal sinus mucocele?
Areas of complete bone resorption may be present, resulting in bony defect and extension of the ‘mass’ into adjacent tissues 2,3. Peripheral calcification is sometimes seen 2. Following administration of contrast, only peripheral enhancement (if any) is seen.
MOST common location of paranasal sinus osteoma and associations
frontal (80%) > ehtmoidal (15%)
Gardners syndrome
type of Schneiderian papilloma, representing an uncommon non-cancerous sinonasal tumour that mostly affects middle-aged men. They occasionally undergo malignant transformation. On imaging, they classically demonstrate a convoluted cerebriform pattern seen on both T2 and contrast-enhanced T1 weighted MRI images.
Inverted papillomas
Males > female
40-60 yrs
MOST common location for Inverted papillomas
Inverted papillomas most commonly occur on the lateral wall of the nasal cavity, most frequently related to the middle turbinate/middle meatus and maxillary ostium, although they are seen elsewhere in the nasal passage. As the mass enlarges it results in bony remodelling and resorption and often extends into the maxillary antrum
Classic imaging feature of inverted papilloma
demonstrates a distinctive appearance, referred to as convoluted cerebriform pattern, seen on both T2 and contrast-enhanced T1 weighted images. This represents alternating lines of high and low signal intensity, the appearance of which has been likened to, albeit loosely, cerebral cortical gyrations. This sign is seen in 50-100% of cases and is uncommon in other sinonasal tumours.
rare benign, but locally aggressive, vascular tumours that occur almost exclusively in young men; usually between the ages of 10 and 18.
Juvenile nasopharyngeal angiofibromas
occur almost exclusively in males and usually in adolescence (~15 years)
The most common of the benign nasopharyngeal neoplasms.
Where do Juvenile nasopharyngeal angiofibromas commonly arise ?
these masses are thought to arise from the region of the sphenopalatine foramen, they are usually sizeable at diagnosis, frequently with extension medially into the nasopharynx, laterally into the pterygopalatine fossa and, over time, beyond into the orbit, paranasal sinuses, intracranial cavity and infratemporal fossa.
Majority of Juvenile nasopharyngeal angiofibromas are supplied by which artery?
external carotid artery
internal carotid artery: less common, usually in larger tumours
rare sub type of sinonasal carcinoma. It is considered a highly aggressive neoplasm arising in the paranasal sinuses.
Where do they arise ?
Sinonasal undifferentiated carcinoma (SNUC)
Most arise within the ethmoid sinuses and superior nasal cavity.
tumours arising from the basal layer of the olfactory epithelium in the superior recess of the nasal cavity.
How do they present?
Olfactory neuroblastomas, also known as esthesioneuroblastomas
(bimodal age distribution )
usually present as a soft tissue mass in the superior olfactory recess involving the anterior and middle ethmoid air-cells on one side and extending through the cribriform plate into the anterior cranial fossa. Contrast enhancement is often marked in both CT and MRI studies.
Prognosis is significantly affected by the presence of distant metastases (see olfactory neuroblastoma staging).
no distant metastases: 60% 5-year survival 6
distant metastases: 0% 5-year survival
What is Acrania anencephaly sequence
progression from a relatively normal-appearing exposed brain due to an absent cranium (acrania) to an amorphous brain mass (exencephaly) to no recognisable brain tissue (anencephaly)
? a chronic granulomatous infection involving the upper respiratory tract due to Klebsiella rhinoscleromatis. It initially involves the nasal mucosa but it may progress to involve any part of the upper respiratory tract
Rhinoscleroma
between 10 to 30 years old. It is endemic in Central America, Egypt, tropical Africa, India, and Indonesia 3.
Characteristic radiological feature of rhinoscleroma
bilateral or unilateral expansile nasal masses, lesions are usually homogeneous, hyperdense and non-enhancing
masses usually extend through the nasal nares anteriorly and into the adjacent paranasal sinuses
lesions line the sinus wall causing bone sclerosis, bone thinning (pressure atrophy) or it may absorb it with extrasinus extension
no bone destruction which helps to differentiate it from malignant lesions
in long standing cases, rhinoscleroma may extend to involve other parts of the upper respiratory tract:
such as pharynx with nodular infiltration of the oropharynx, tonsillar bed, soft and hard palate
may also show laryngotracheal involvement, the usual site of laryngeal involvement is the glottic–subglottic region showing concentric narrowing of the airway, thickening of the tracheal wall and nodular thickening of the tracheal mucosa
